PROJECT SUMMARY Multi-level implementation strategies targeting parents and health care providers have potential to substantially increase the low human papillomavirus (HPV) vaccination rates among the targeted age group of 11- to 12-year-olds. Florida adolescents are particularly vulnerable due to the state?s rank of 4th for HPV- related cancer diagnoses, but 39th for HPV vaccine initiation and up-to-date rates. The problem addressed by this proposal is the need for more effective and pragmatic preventive interventions to increase provider HPV vaccine recommendations. Existing interventions increase HPV vaccine rates only moderately (approximately 5 to 15 percentage points). A multi-leveled focus on provider recommendations and parent receptiveness is warranted because 90% of unvaccinated teens actually had well visits, provider recommendations increase HPV vaccination rates 9- to 170-fold, and parents make vaccine decisions. Additionally, national health agencies endorse two approaches for recommendation: mentioning HPV as one of the needed adolescent vaccines (bundled) or emphasizing the HPV vaccine benefits (benefits). Yet, the relative effectiveness of recommendation approaches and effectiveness of approach concordance across provider-parent levels is unclear. The goal of the proposal is to evaluate the effectiveness of a multi-level (provider and parent) intervention of two implementation strategies (brief provider training and parent-targeted interactive text message reminders) on HPV vaccination rates among 11- to 12-year-old boys and girls. Guided by the Integrated Behavior Model, a meta-theory combining the Theory of Reasoned Action, the Social Cognitive Theory, and the Theory of Planned Behavior, the central hypotheses are that brief provider trainings will increase providers? intentions to recommend the HPV vaccine and the parent-targeted interactive text messages will increase parents? salience. Specific Aims are to: (1) To test the overall effectiveness of brief provider trainings with an embedded comparison of bundled and benefits approaches. (2) To test the overall effectiveness of interactive text messages for parents with an embedded comparison of bundled and benefits approaches. (3) Evaluate the effectiveness of the combined brief provider trainings and interactive text messages for parents with an embedded comparison of concordant and distinct approaches. (4) Evaluate moderation of the implementation strategies? effectiveness by clinical practice factors. Hypotheses will be evaluated with a doubly randomized, two-level nested design for testing two nested implementation factors (provider training and parent text messaging with bundled or benefits approaches). Thirty clinics will be recruited from the OneFlorida Clinical Research Consortium. The innovations are the factorial-designed evaluation estimating the value-added of multi-level implementation and the evaluation of concordant recommendation approaches across provider- and parent-levels. The significance lies in the potential to lead the field closer to a sustainable, scalable, and efficacious approach to decreasing HPV-related cancer rates.